There are two types of data for storing or registering a configuration, that is, raster type and vector type. The vector type data, particularly the peripheral vector data is useful because it is smaller in volume than the raster data, as well as easily rotatable and changeable in size.
Vector data is defined by a train of a part of boundary pixels of a configuration, so the quality of the reappeared configuration depends on selection of boundary pixels.
In the case of character vectorizing, such as Chinese character's vectorizing, the reappearance quality is very important because the product's value mainly depends on the reappearance quality.
As far as the inventor knows, conventional vectorizing method comprises angular calculations between pairs of boundary pixels of a configuration. Since the angular calculation is floating point calculation, it takes long time to select boundary pixels.
Furthermore, it is difficult to find and define a corner point on a right angle concavity.